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Thread: Chaining Grounds Together (switches) - bigger awg needed?

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    Default Chaining Grounds Together (switches) - bigger awg needed?

    Just wiring up my switches and wondering if chaining the grounds together requires a larger ground than the (+) due to the total possible current going through? I suspect yes? Should I just add up the total possible and use appropriate ground size?
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    Default Re: Chaining Grounds Together (switches) - bigger awg needed?

    I would use a ground bus, and ground to that, chaining grounds together is asking for trouble ...
    At least if my understanding of what you are doing is correct. (i.e. a sequential chain)

    Run a decent size main ground lead to a terminal block (maybe 12-14 awg), and then connect your
    independent grounds to it. Something like this, with wire sized accordingly.

    Just think hub and spokes, and the main ground wire goes to the hub.

    Jeff

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    Senior Member efwd's Avatar
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    Default Re: Chaining Grounds Together (switches) - bigger awg needed?

    I have had one ground wire break off at the ground bus so far. Apparently crimped too tightly. Imagine if this sort of thing happens with a daisy chain ground.
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    Senior Member jrevens's Avatar
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    Default Re: Chaining Grounds Together (switches) - bigger awg needed?

    Quote Originally Posted by tracstarr View Post
    Just wiring up my switches and wondering if chaining the grounds together requires a larger ground than the (+) due to the total possible current going through? I suspect yes? Should I just add up the total possible and use appropriate ground size?
    Don't "daisy chain" them, but I think you are possibly talking about a common buss bar or wire across a group of switches. That is fine, and the buss bar (or wire links) needs to be sized to accommodate the total potential load. However, you don't normally switch the ground circuit. The switches will be on the positive side of the circuits. Like Jeff said, if you have multiple smaller ground wires going to a "hub" or terminal strip, the "main" wire connected to that strip and ultimately connected to the negative terminal of the battery needs to be properly sized to handle the total potential load of all the circuits combined. I would recommend getting a good book, like "AeroElectric Connection", and studying it. It would be a good resource for you and it is available online as a free download.
    Last edited by jrevens; 12-11-2019 at 09:40 AM.
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    Super Moderator desertdave's Avatar
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    Default Re: Chaining Grounds Together (switches) - bigger awg needed?

    Previous hobby I rebuilt Land Rover Defenders. Every joke ever made about Land Rovers are about leaks and electrical issues. 99% of the electrical issued were because of bad DAISY CHAIN grounds. #friendsdontletfriendsdaisychaingrounds
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    Default Re: Chaining Grounds Together (switches) - bigger awg needed?

    Yeah I have a main ground block already. I was more thinking about the bus bars I see used for switches which then go to main ground block. And doing that with wire. But sounds like I should either get a bar or run individual grounds.
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    Default Re: Chaining Grounds Together (switches) - bigger awg needed?

    Just the start of my rewiring. No more daisy chain/ground loop mess,


    Screen Shot 2019-12-11 at 3.04.59 PM.png

    There is logic behind the madness. Everything labeled 1-10 will be accessories (Keyed power) , 20-29 Ignition, 30-39 Radio (Which has its own ground for all the shielding wires)

    Each circuit breaker and switch is individually wired. (Still just laying things out here, and testing the dash template)
    Screen Shot 2019-12-11 at 3.12.40 PM.jpg
    Last edited by 4Hummer; 12-11-2019 at 01:17 PM.

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    Senior Member jrevens's Avatar
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    Default Re: Chaining Grounds Together (switches) - bigger awg needed?

    Quote Originally Posted by tracstarr View Post
    Yeah I have a main ground block already. I was more thinking about the bus bars I see used for switches which then go to main ground block. And doing that with wire. But sounds like I should either get a bar or run individual grounds.

    Sent from my SM-G973W using Tapatalk
    I think there may by a little confusion with terminology. The bus bars used for switches don't then go to a "main ground block". A "ground block" would denote a common "block" of connection points that is connected to ground (neg.). Switches normally switch the positive (+) side of the circuit. There is nothing inherently wrong with connecting them together with wire instead of a bar.
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    Default Re: Chaining Grounds Together (switches) - bigger awg needed?

    Thanks. I just ran individual grounds.
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